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Stability of Numerical Interface Conditions for Fluid/Structure Interaction

Description: In multi physics computations, where a compressible fluid is coupled with a linearly elastic solid, it is standard to enforce continuity of the normal velocities and of the normal stresses at the interface between the fluid and the solid. In a numerical scheme, there are many ways that the velocity- and stress-continuity can be enforced in the discrete approximation. This paper performs a normal mode analysis to investigate the stability of different numerical interface conditions for a model p… more
Date: August 13, 2009
Creator: Banks, J W & Sjogreen, B
Partner: UNT Libraries Government Documents Department
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A High-Resolution Godunov Method for Compressible Multi-Material Flow on Overlapping Grids

Description: A numerical method is described for inviscid, compressible, multi-material flow in two space dimensions. The flow is governed by the multi-material Euler equations with a general mixture equation of state. Composite overlapping grids are used to handle complex flow geometry and block-structured adaptive mesh refinement (AMR) is used to locally increase grid resolution near shocks and material interfaces. The discretization of the governing equations is based on a high-resolution Godunov method,… more
Date: February 13, 2006
Creator: Banks, J W; Schwendeman, D W; Kapila, A K & Henshaw, W D
Partner: UNT Libraries Government Documents Department
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A Study of Detonation Propagation and Diffraction with Compliant Confinement

Description: A previous computational study of diffracting detonations with the ignition-and-growth model demonstrated that contrary to experimental observations, the computed solution did not exhibit dead zones. For a rigidly confined explosive it was found that while diffraction past a sharp corner did lead to a temporary separation of the lead shock from the reaction zone, the detonation re-established itself in due course and no pockets of unreacted material were left behind. The present investigation c… more
Date: August 13, 2007
Creator: Banks, J; Schwendeman, D; Kapila, A & Henshaw, W
Partner: UNT Libraries Government Documents Department
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Laser Safety Inspection Criteria

Description: A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 1.3.2.8, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of th… more
Date: June 13, 2005
Creator: Barat, K.
Partner: UNT Libraries Government Documents Department
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Limiting Future Proliferation and Security Risks

Description: A major new technical tool for evaluation of proliferation and security risks has emerged over the past decade as part the activities of the Generation IV International Forum. The tool has been developed by a consensus group from participating countries and organizations and is termed the Proliferation Resistance and Physical Protection (PR&PP) Evaluation Methodology. The methodology defines a set of challenges, analyzes system response to these challenges, and assesses outcomes. The challe… more
Date: March 13, 2011
Creator: Bari, R.
Partner: UNT Libraries Government Documents Department
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Generation IV PR and PP Methods and Applications

Description: This paper presents an evaluation methodology for proliferation resistance and physical protection (PR&PP) of Generation IV nuclear energy systems (NESs). For a proposed NES design, the methodology defines a set of challenges, analyzes system response to these challenges, and assesses outcomes. The challenges to the NES are the threats posed by potential actors (proliferant States or sub-national adversaries). The characteristics of Generation IV systems, both technical and institutional, a… more
Date: October 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
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MARKOV Model Application to Proliferation Risk Reduction of an Advanced Nuclear System

Description: The Generation IV International Forum (GIF) emphasizes proliferation resistance and physical protection (PR&PP) as a main goal for future nuclear energy systems. The GIF PR&PP Working Group has developed a methodology for the evaluation of these systems. As an application of the methodology, Markov model has been developed for the evaluation of proliferation resistance and is demonstrated for a hypothetical Example Sodium Fast Reactor (ESFR) system. This paper presents the case of diver… more
Date: July 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
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Study of Risk Assessment Programs at Federal Agencies and Commercial Industry Related to the Conduct or Regulation of High Hazard Operations

Description: In the Department of Energy (DOE) Implementation Plan (IP) for Defense Nuclear Facilities Safety Board's Recommendation 2009-1, the DOE committed to studying the use of quantitative risk assessment methodologies at government agencies and industry. This study consisted of document reviews and interviews of senior management and risk assessment staff at six organizations. Data were collected and analyzed on risk assessment applications, risk assessment tools, and controls and infrastructure supp… more
Date: March 13, 2011
Creator: Bari, R.; Rosenbloom, S. & O'Brien, J.
Partner: UNT Libraries Government Documents Department
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Anomalous gauge boson couplings

Description: The measurement of anomalous gauge boson self couplings is reviewed for a variety of present and planned accelerators. Sensitivities are compared for these accelerators using models based on the effective Lagrangian approach. The sensitivities described here are for measurement of {open_quotes}generic{close_quotes} parameters {kappa}{sub V}, {lambda}{sub V}, etc., defined in the text. Pre-LHC measurements will not probe these coupling parameters to precision better than O(10{sup -1}). The LHC s… more
Date: January 13, 1997
Creator: Barklow, T.; Rizzo, T. & Baur, U.
Partner: UNT Libraries Government Documents Department
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Theory and Simulation of Warm Dense Matter Targets

Description: We present simulations and analysis of the heating of warm dense matter foils by ion beams with ion energy less than one MeV per nucleon to target temperatures of order one eV. Simulations were carried out using the multi-physics radiation hydrodynamics code HYDRA and comparisons are made with analysis and the code DPC. We simulate possible targets for a proposed experiment at LBNL (the so-called Neutralized Drift Compression Experiment, NDCXII) for studies of warm dense matter. We compare the … more
Date: July 13, 2006
Creator: Barnard, J. J.; Armijo, J.; More, R. M.; Friedman, A.; Kaganovich, I.; Logan, B. G. et al.
Partner: UNT Libraries Government Documents Department
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Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter

Description: One approach for heating a target to ''Warm Dense Matter'' conditions (similar, for example, to the interiors of giant planets or certain stages in Inertial Confinement Fusion targets), is to use intense ion beams as the heating source (see refs.[6] and [7] and references therein for motivation and accelerator concepts). By consideration of ion beam phase space constraints, both at the injector, and at the final focus, and consideration of simple equations of state and relations for ion stoppin… more
Date: May 13, 2005
Creator: Barnard, J. J.; Briggs, R. J.; Callahan, D. A.; Davidson, R. C.; Friedman, A.; Grisham, L. et al.
Partner: UNT Libraries Government Documents Department
open access

Beam dynamics studies for heavy ion fusion drivers

Description: No Description Available.
Date: April 13, 1999
Creator: Barnard, J.; Celata, C.; Craig, G.; Dehoon, M.; Faltens, A.; Friedman, A. et al.
Partner: UNT Libraries Government Documents Department
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Progress in rapid detection and identification of unknown human and agricultural pathogens

Description: The medical industry is driving pathogen detection technology from its present characteristics of $50/sample, 100 sample capability systems, with several day time responses, having several percent error rates in reported outcomes. The systems described above are capable of providing samples at < $5/test, managing several million samples, < 1-hour cycle times, (or just minutes in some cases) and < 0.1% error rates. Because of their importance to the medical and agricultural communities,… more
Date: August 13, 1999
Creator: Barnes, T; Holzrichter, J F & Milanovich, F P
Partner: UNT Libraries Government Documents Department
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High-Efficiency Resonant Cavity Quadrupole Moment Monitor

Description: Measurement of the beam quadrupole moment at several locations can be used to reconstruct the beam envelope and emittance parameters. The measurements can be performed in a non-intercepting way using a set of quadrupole-mode cavities. We present a cavity design with an optimized quadrupole moment shunt impedance. The cavity properties can be characterized using a wire test method to insure symmetry about the central axis, and alignment to nearby position sensing cavities. The design and charact… more
Date: April 13, 2007
Creator: Barov, N.; Nantista, C. D.; Miller, R. H. & Kim, J. S.
Partner: UNT Libraries Government Documents Department
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A Hidden Twelve-Dimensional SuperPoincare Symmetry In Eleven Dimensions

Description: First, we review a result in our previous paper, of how a ten-dimensional superparticle, taken off-shell, has a hidden eleven-dimensional superPoincare symmetry. Then, we show that the physical sector is defined by three first-class constraints which preserve the full eleven-dimensional symmetry. Applying the same concepts to the eleven dimensional superparticle, taken off-shell, we discover a hidden twelve dimensional superPoincare symmetry that governs the theory.
Date: December 13, 2003
Creator: Bars, Itzhak; Deliduman, Cemsinan; Pasqua, Andrea & Zumino, Bruno
Partner: UNT Libraries Government Documents Department
open access

Ultrafast magnetization dynamics studies using an x-ray streakcamera

Description: The spin dynamics of ferromagnetic thin films following an excitation by ultrashort 100-fs near-infrared laser pulses has recently received much attention. Here, a new approach is described using x-ray magnetic circular dichroism to investigated emagnetization and magnetization switching processes. In contrast to magneto-optical measurements, x-ray dichroism has the advantage of determining separately the spin and orbital components of the magnetic moment. The relatively low time resolution of … more
Date: July 13, 2005
Creator: Bartelt, A. F.; Comin, A.; Feng, J.; Nasiatka, J.; Padmore, H. A.; Scholl, A. et al.
Partner: UNT Libraries Government Documents Department
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Sensitivity and uncertainty investigations for Hiroshima dose estimates and the applicability of the Little Boy mockup measurements

Description: This paper describes sources of uncertainty in the data used for calculating dose estimates for the Hiroshima explosion and details a methodology for systematically obtaining best estimates and reduced uncertainties for the radiation doses received. (ACR)
Date: September 13, 1983
Creator: Bartine, D. E. & Cacuci, D. G.
Partner: UNT Libraries Government Documents Department
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Promoting bioanalytical concepts in genetics: A TATA box molecularly imprinted polymer as a small isolated fragment of the DNA damage repairing system

Description: Article describes study which demonstrates that a new, stable, artificial TATA (T — thymine, A — adenine) box is recognized by amino acids recognizing the natural TATA box.
Date: February 13, 2019
Creator: Bartold, Katarzyna; Pietrzyk-Le, Agnieszka; Lisowski, Wojciech; Golebiewska, Karolina; Siklitskaya, Alexandra; Borowicz, Pawel et al.
Partner: UNT College of Science
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Electron Bunch Profile Diagnostics in the Few FS Regime Using Coherent Smith-Purcell Radiation

Description: The rapid developments in the field of laser-driven particle acceleration hold the prospect of intense, highly relativistic electron bunches that are only a few fs long. The determination of the temporal profile of such bunches presents new challenges. The use of a radiative process such as Smith-Purcell radiation (SPR), is particularly promising in this respect. In this technique the beam is made to radiate a small amount of e/m radiation and the temporal profile is reconstructed from the meas… more
Date: December 13, 2011
Creator: Bartolini, R.; Source, /Oxford U. /Diamond Light; Clarke, C.; /SLAC; Delerue, N.; /Orsay, LAL et al.
Partner: UNT Libraries Government Documents Department
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Sensitivity of numerical dispersion modeling to explosive source parameters

Description: The calculation of downwind concentrations from non-traditional sources, such as explosions, provides unique challenges to dispersion models. The US Department of Energy has assigned the Atmospheric Release Advisory Capability (ARAC) at the Lawrence Livermore National Laboratory (LLNL) the task of estimating the impact of accidental radiological releases to the atmosphere anywhere in the world. Our experience includes responses to over 25 incidents in the past 16 years, and about 150 exercises … more
Date: February 13, 1991
Creator: Baskett, R.L. (EG and G Energy Measurements, Inc., Pleasanton, CA (USA)) & Cederwall, R.T. (Lawrence Livermore National Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
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Crystalline silicon processing

Description: This presentation (consisting of vugraphs) first provides the background motivation for Sandia`s effort for the development of improved crystalline silicon solar cells. It then discusses specific results and progress, and concludes with a brief discussion of options for next year.
Date: July 13, 1994
Creator: Basore, P. A.
Partner: UNT Libraries Government Documents Department
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